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#Diy collinear wifi antenna update#
#Diy collinear wifi antenna driver#
#Diy collinear wifi antenna tv#

Next, the tip section is also 114.3mm which is 82% of a half wave, and there is no reason for it to be less than a half wave and better approach the objective of a current minimum at each of the 8 feed points that appear in parallel due to the interior electrical length of the sections and the transpositions.Īs mentioned, ignoring the effects of coax loss, we effectively have 8 current minimum or high impedance feed points in parallel, and this would be the impedance seen by the feed line entering the bottom transposition. This is a common compromise, and not too severe in the resultant degradation. Obviously that is not possible unless the coax has vf=1, and the designer has chosen a compromise where the drive phasing is approximately correct and the exterior sections are 82% of a half wave. Lets call them a half wave interior electrical length.įor this type of antenna to be co-phased (or in-phase), the crossover points need to be at current minima on the exterior surface and an electrical half wave apart on the interior. Looking at the middle sections first, they are 4.5″ or 114.3mm or 182.45° if made from Belden 1694A RG6 coax.

#Diy collinear wifi antenna tv#

Robert Nickels, W9RAN shows a design for an “8 element colinear vertical” for 1090MHz ADSB in QST Jan 2014 in his article Virtual Radar From a TV Dongle.

Center-Fed Dipole : elements length for a Z=200 +/- 0j ohms.

Another small efficient matching transformer for an EFHW – 2643251002 – #4 – a paired Guanella 1:1 balun.

(tr)uSDX – review of the directional coupler ADC design.

NanoVNA-H* – my method for firmware updates.

RF Power Meter 2 (RFPM2) – 40dB external attenuator calibration and integration.

NanoVNA-H4 – battery charge from discharged.

ISP programming of the (tr)uSDX – more on SPI.

AT-100 ATU Sontheimer coupler using a single binocular ferrite core.

How important is directional coupler Directivity?.

Digital display for Revex W560 directional wattmeter – part 1.

Digital display for VK-AMPS 2kW directional coupler – part 1.

Digital display for QRP labs 20W dummy load – part 1.

#Diy collinear wifi antenna update#

NanoVNA-H* – a howto do firmware update using STM32CubeProgrammer.NanoVNA-H – modification of v3.3 PCB to start the bootloader from the jog switch.Digital display for QRP labs 20W dummy load – part 2.Digital display for half wave detector with cubic spline interpolation – part 1.Digital display for half wave detector with cubic spline interpolation – part 2.Implementation of G5RV inverted V using high strength aluminium MIG wire – 5 year review.Digital display for half wave detector with cubic spline interpolation – part 3.Digital display for half wave detector with cubic spline interpolation – part 4.Trying to make sense of Nanosaver’s R/ω and jX/ω graph.Digital display for DIY 25W dummy load – part 1.Digital display for DIY 25W dummy load – part 2.(tr)uSDX bootloader corruption – a smoking gun.

(tr)uSDX bootloader corruption – a smoking gun – an experiment.Chinese 3.0V 16340 CR2 Lithium Ion batteries.Chinese 9.6V 700mAh Tamiya style battery pack.SNTP synchronised clock v0.04 – beta release.(tr)uSDX firmware, bootloader, application – an explanation.

#Diy collinear wifi antenna driver#

LED plate driver failure – 24W round plate.

FT37-43 for a 49:1 EFHW transformer enquiry.

Digital display for DIY 25W dummy load – part 3.

Neewer Macro LED Ring Light Flash RF550 – Guide Number.

EARU Programmable Thermocouple K J PT100 to 4-20mA Converter TC RTD Input 4-20mA Output Head-mounted Temperature Transducer – first impressions.

Setting a torque wrench when using an offset adapter.

CG K/ J/ S/ B to 4-20mA 0-1800 Celsius Thermocouple Converter TC Input 4-20mA Output Head-mounted Temperature Transducer – first impressions.

What kind of balun is this? Is it any good?.

Digital display for DIY 25W dummy load – part 4.

Garden environmental telemetry project – part 1.

Diagnosis of a 9:1 transformer from NanoVNA plot.

Diagnosis of a 9:1 transformer from NanoVNA plot – part 2.